Metal artifact reduction techniques for single energy CT and dual-energy CT with various metal materials.

OBJECTIVE: The aim of the current study is to evaluate the effectiveness of reduction metal artifacts using kV-CT image with the single-energy based metal artefact reduction (SEMAR) technique by single-energy reconstruction, monochromatic CT and rED reconstructed by dual-energy reconstruction. METHODS: Seven different metal materials (brass, aluminum, copper, stainless, steel, lead and titanium) were placed inside the water-based PMMA phantom. After DECT-based scan, the artefact index (AI) were evaluated with the kV-CT images with and without SEMAR by single-energy reconstruction, and raw-data based electron density (rED), monochromatic CT images by dual-energy reconstruction. Moreover, the AI with evaluated with rED and the converted ED images from the kV-CT and monochromatic CT images. RESULTS: The minimum average value of the AI with all-metal inserts was approximately 80 keV. The AI without SEMAR was larger than that with SEMAR for the 80 kV and 135 kV CT images. In the comparison of the AI for the rED and ED images that were converted from 80 kV and 135 kV CT images with and without SEMAR, the monochromatic CT images of the PMMA phantom with inserted metal materials at 80 keV revealed that the kV-CT with SEMAR reduced the metal artefact substantially. CONCLUSION: The converted ED from the kV-CT and monochromatic CT images could be useful for a comparison of the AI using the same contrast scale. The kV-CT image with SEMAR by single-energy reconstruction was found to substantially reduce metal artefact. ADVANCES IN KNOWLEDGE: The effectiveness of reduction of metal artifacts using single-energy based metal artefact reduction (SEMAR) technique and dual-energy CT (DECT) was evaluated the electron density conversion techniques.

Impact of our new protocol on the outcome of the neonates with congenital diaphragmatic hernia.

BACKGROUND/PURPOSE: Congenital diaphragmatic hernia (CDH) remains a defiant challenge for pediatric surgeons. Since 2003, we developed a new protocol aiming for the better outcome. In this study, the usefulness of our new protocol was evaluated. MATERIALS AND METHODS: Forty-six neonates with CDH at the age of less than 24 h were divided into two groups based on the difference of era and treatment protocols. In Group 1, 15 patients were treated between 1997 and 2002 and 31 patients were treated between 2003 and 2011 in Group 2. In the latter group, a new protocol was introduced focusing on the prevention of lung edema as well as lung injury by steroid administration and on the stabilization of cardiopulmonary function using continuous D-mannitol infusion. The survival rate and the postoperative intubation period (POIP) were compared between the two groups. RESULTS: The overall survival rate was significantly increased from 53 % (8/15) to 81 % (25/31) (p < 0.05). In isolated CDH, the survival rate was increased from 58 to 93 %. The average POIP was remarkably shortened from 39.0 to 4.4 days (p < 0.01). CONCLUSION: Our new protocol remarkably improved the survival rate and shortened the period of mechanical ventilation in neonates with CDH.

Gene regulatory network of unfolded protein response genes in endoplasmic reticulum stress.

In the endoplasmic reticulum (ER), secretory and membrane proteins are properly folded and modified, and the failure of these processes leads to ER stress. At the same time, unfolded protein response (UPR) genes are activated to maintain homeostasis. Despite the thorough characterization of the individual gene regulation of UPR genes to date, further investigation of the mutual regulation among UPR genes is required to understand the complex mechanism underlying the ER stress response. In this study, we aimed to reveal a gene regulatory network formed by UPR genes, including immunoglobulin heavy chain-binding protein (BiP), X-box binding protein 1 (XBP1), C/EBP [CCAAT/enhancer-binding protein]-homologous protein (CHOP), PKR-like endoplasmic reticulum kinase (PERK), inositol-requiring 1 (IRE1), activating transcription factor 6 (ATF6), and ATF4. For this purpose, we focused on promoter-luciferase reporters for BiP, XBP1, and CHOP genes, which bear an ER stress response element (ERSE), and p5 × ATF6-GL3, which bears an unfolded protein response element (UPRE). We demonstrated that the luciferase activities of the BiP and CHOP promoters were upregulated by all the UPR genes, whereas those of the XBP1 promoter and p5 × ATF6-GL3 were upregulated by all the UPR genes except for BiP, CHOP, and ATF4 in HeLa cells. Therefore, an ERSE- and UPRE-centered gene regulatory network of UPR genes could be responsible for the robustness of the ER stress response. Finally, we revealed that BiP protein was degraded when cells were treated with DNA-damaging reagents, such as etoposide and doxorubicin; this finding suggests that the expression level of BiP is tightly regulated at the post-translational level, rather than at the transcriptional level, in the presence of DNA damage.

Lentinan prolonged survival in patients with gastric cancer receiving S-1-based chemotherapy.

AIM: To examine whether administration of lentinan, purified ß-1, 3-glucan, can prolong survival in advanced gastric cancer patients receiving S-1-based chemotherapy. METHODS: Since 2004, 78 patients with metastatic or recurrent gastric cancer have received S-1-based chemotherapy as first-line treatment. Survival, side effects, and the ratio of granulocytes/lymphocytes (G/L ratio) were compared between 2 groups of patients who received chemo-immunotherapy using lentinan and chemotherapy alone. RESULTS: Median overall survival was significantly longer in the former group than in the latter group [689 d (95% CI: 431-2339 d) vs 565 d (95% CI: 323-662 d), P = 0.0406]. In addition, the G/L ratio in patients who received lentinan was maintained around or below 2, which was significantly lower than that in patients who received chemotherapy alone (P < 0.001). CONCLUSION: Chemo-immunotherapy with lentinan offers a significant advantage over S-1-based chemotherapy alone in terms of survival in patients with advanced gastric cancer.

[Combination therapy of S-1 and 24-h infusion of cisplatin after palliative gastrectomy for stage IV gastric cancer].

We prospectively analyzed the adverse effects and outcomes of 15 patients with stage IV gastric cancer who underwent palliative gastrectomy from December, 2002 to May, 2008 and subsequently received combination therapy of S-1 and 4-h infusion of cisplatin. The National Cancer Institute common toxicity criteria (version 3. 0) were applied to evaluate the adverse effects of this therapy, and the Kaplan-Meier method was used to plot the survival curve. The side effects most frequently observed were anorexia (grade 3; 33%), although one case of grade 4 who was easily fatigued was noted during the first course and could not receive further courses of this therapy. The 2-year survival rate was 33% and median survival time was 31 months. It has been suggested that 24-h infusion of cisplatin combined with oral S-1 after reduction surgery might improve survival in patients with stage IV gastric cancer.

Pathological complete response induced by the combination therapy of S-1 and 24-h infusion of cisplatin in two cases initially diagnosed as inoperable advanced gastric cancer.

We report on two patients, successfully treated by the combination therapy of S-1 and 24-h infusion of cisplatin (CDDP), who were initially diagnosed with unresectable stage 4 advanced gastric cancer. Each patient had a very good clinical response and underwent curative gastrectomy after completion of 14 and 10 courses of S-1/CDDP chemotherapy, respectively. A microscopically detailed examination of surgically obtained specimens showed the complete disappearance of malignant cells in the two cases. S-1/CDDP combination therapy can, therefore, be highly active in incurable advanced gastric carcinoma.

Reactive angioendotheliomatosis of the intestine.

We present a case of reactive angioendotheliomatosis (RAE) of the colon, featuring intravascular proliferation of endothelial cells with histologic resemblance to glomeruloid hemangioma. A 19-year-old Japanese male with an anal fistula was diagnosed endoscopically with Crohn's disease. Six months later, he was hospitalized for fever and abdominal pain. Emergency resection of ileocecum and splenic flexure of the colon was undertaken to control massive intestinal hemorrhage, and in all parts of the resected colon, foci of many small vessels with intravascular proliferation of endothelial cells were noted throughout the layers. Moreover, solid proliferation of endothelial cells was seen in the submucosa at the base of open ulcers. Two small granulomas, compatible with Crohn's disease, were also evident in the muscle layer of the terminal ileum. No other hemangiomas or hemangioma-like structures were observed with CT scans, and the vascular lesions were histologically diagnosed as RAE. The pathogenesis of this disorder is unknown, and most cases occur in skin with systemic disease. The present case might thus be a first case of RAE of the intestine without cutaneous involvement. Whether there is a relation with coexistent enteritis suggestive of Crohn's disease needs to be clarified.